Heat exchange unit



Feb. 27, 1940. E. s. CORNELL, JR

HEAT EXCHANGE UNIT 4 Sheets-Sheet 1 Filed July 31, 1937 lNVENTOR Edward 5. Cor

lZa

nell Jr. I

E'QNEY J Feb. 27, 1940. 5 L JR 2,191,519

HEAT EXCHANGE UNIT Filed July 31, 1937 4 ShSBtS-ShGGt 2 w '04 I04, T 10 lo- Edward 5. Come Jr.

w gfm HIS T RNEY Fell 1940- E. s. CORNELL, JR

HEAT EXCHANGE UNIT Filed July 31, 1937 4 Sheets-Sheet 3 INVENTOR Edward SCQrnQILJrI v H1 1 I QRNEY Feb. 27, s E JR 2,191,519

HEAT EXCHANGE UNIT Filed July 31, 1937 4 Sheets-Sheet 4 INVENTQR Patented Feb. 27, 1940 PATENT orrlcs HEAT EXCHANGE UNIT Edward S. Cornell, Jr., Larchmont, N. Y., assignor, by mesne assignments, to American Radiator '8; Standard Sanitary Corporation, New York, N. Y., a corporation of Delaware Application July 31, 1937, Serial No. 156,689

12 Claims.

This invention relates to heat exchangers, and to thermal systems in which the heat exchangers are incorporated.

In particular the invention relates to heat exchangers of the radiant convector type, and to thermal systems wherein such heat exchangers.

are supplied with a fluid heating medium or a fluid cooling medium within the confines of fluid flow passages.

An outstanding feature of heat exchangers of the above type followingprinciples of the present invention, is the cooperative association of a radiant convector having, relatively low thermal conductivity, with a radiant convector having relatively high thermal conductivity. The association is advantageously such that the former radiant convector serves to initiate and direct flow,

stacks extending substantially horizontally across Preferably it isthe collective stack openings. located intermediate the vertical extent of the radiant convector of low thermalconductivity, intercepting theair-flow passages, i. e., stacks.

It is desirable that the-radiant convector of low thermal conductivity be cast from iron, preferably in the form of similar sections, which, when joined, collectively provide substantially plane outer faces adapting the heat exchange unit for radiant heating per se in addition to convection heating.

The radiant convector of high thermal conductivity is desirably of copper or of a copper alloy provided with extended fins affording a considerable area of heat exchange surface.

The thermal system of the invention provides for the supply of a fluid heating medium such 50 as hot water or steam to both the radiant convectors of the heat exchangeunit or units whenever appropriate, regulation of supply being had .by suitable valves.

Convection currents of airare readily engen- It is advantageously located in the tiered by the radiant cast iron, thereby effecting air flow upwardly through the stacks, passing over and in intimate contact with the heat exchange surfaces of the copper radiant convector. Since the relatively high thermal conductivity of copper imparts great capacity for ther- 5 mal interchange, the above describedcombination is particularly effective and eflicient for the thermal treatment and circulation of air. Once circulation through the thermal unit is initiated, the copper radiant convector functions as a pril0 mary circulator, boosting the velocity of circulation proportionally to the rate of heat'interchange.

When appropriate, supply of heating fluid to the radiant convectors may be cut oil and by proper valve regulation, supply of cooling fluid may be effected sol to the convector of high thermal conductivity, e.,,the copper convector.

By suitable provided instrumentalities, the flow of a forced supply of air, conditioned or otherwise, may be directed 0 er the heat exchange sur faces of the convector 0 high thermal conductivity intimately contact'ng such heat exchange surfaces in effecting heat transference therebetween, and, in the case of heat interchange from. the surfaces to the flowing air, enhancing the rate of air circulation. Such forced supply of air is effective to provide superheating when desired and is essential for the promotion of air circulation when the heat exchange unit is used for cooling. As an additional feature, such forced supply of air may be employed merely for circulating ,air in thercom or other enclosure in which such heat interchange unit is located, without thermal treatment, when the normal temperature of the room air is as desired. Under such conditions, of course, neither heating nor cooling fluid will be supplied to the radiant con- .vectors. They remain dormant.

Provision may be made, preferably adjacent the 40 location of discharge from the heat exchange unit of the thermally treated or merely circulated air, for the admixture of fresh atmospheric air as and when desired. Embodiments of the invention pursuant to the structural characteristics generically outlined above afford a substantially complete range of thermal treatment for air, being particularly advantageous for use in hotels," apartments, or other buildings presenting a multitude of rooms whose 0- space is at a premium. Heating, cooling, and ventilating are accomplished :as and when requiredv through heat exchange units which are individually all inclusive and dim rnsionally compact.

In the drawings: 9

Fig. 1 represents a front elevation of a preferred embodiment of the heat exchange unit of the present invention. Portions of the front wall are broken out revealing portions of the internal structure in section;

Fig. 2 represents a horizontal section taken on the line 22 of Fig. 1;

Fig. 3 represents a vertical section taken on the line 3-3 of Fig. 1;

Fig. 4 represents a vertical section taken on the line l4 of Fig. 1;

Fig. 5 illustrates several of the heat exchange units of Fig. 1 incorporated in a preferred embodiment of the thermal system of the present invention;

Fig. 6 is a view similar to that of Fig. 1, but illustrating a slightly different embodiment of the invention;

Fig. '7 represents a fragmentary vertical section taken on the line II of Fig. 6; and

Fig. 8 is a view similar to Fig. '7, but illustrating a slightly different arrangement of parts.

Referring to the drawings, and particularly to Figs. 1 through 4:-the heat exchange unit of Fig. 1 comprises a-- radiant convector of relatively low thermal conductivity associated with a radiant convector of relatively high thermal conductivity, the former being indicated by the numeral I 0, and the latter by the numeral II.

The radiant convector I 0 is, in the present instance, assembled from cast iron sections. Those intermediately located in the assembly, and similarly configurated for mutual joinder, are designated I2. Those serving to cap the ends are each configurated on one lateral side for joinder with the assembled intermediate units I2, and on the other lateral side for completing the external configuration of the heat exchange unit per se. They are designated l3 and I4, respectively.

The intermediate sections I2 are substantially I shape and hollow, see Fig. 2, providing passages l5 for the flow of a fluid heating medium. Their front and rear end faces are preferably plane as illustrated, having complementary formations at their edges. Such complementary formations may take the form of tongues and grooves, the tongues of one section, on assembly of the sections, interlocking with the grooves of the adjacent sections to form overlap joints I2a.

I Continuity of front and rear facing of the heat exchange unit is provided by the collective extents of the front and rear faces of the assembled sections. Exterior facial continuity is desirable from the standpoint of appearance, affording a panel surface which may be finished by application of a decorative coating material. The panel nature of the surface provides for radiant heating by the unit, suppassages I6 for adding to the normal heat exchange surface of the passage walls.

The end sections I3 and I4 are formed longer than are the intermediate sections I2. Each hasone lateral wall conflgurated similarly to 'ing apertures of contiguous sections.

the lateral configuration of a section I 2 for cooperation therewith in forming an air-flow passage I6, but has the other lateral walls planar, as illustrated, for completing the external contour of the heat exchange unit.

The intermediate sections l2 are united side by side in vertical coextension, preferably by means of sleeves I'I fitting into suitable register- The longer end sections l3 and I4 are united to the assembled intermediate sections I2 also by means of sleeves H, but are so disposed vertically with respect to such intermediate sections and to each other as to form bottom extensions I3a and Ma, respectively, serving as feet for the heat exchange unit, and top extensions I31) and lb, respectively, serving to receive suitable air outlet means, hereinafter described. Elevation of the intermediate sections from the surface'supporting the heat exchange unit, accomplished by means of the feet I3a and [4a, provides a bottom air inlet opening I8, see Fig. 1, extending transversely of the unit and leading to the air-flow passages, i. e., stacks I6.

A cover element l0l, preferably of sheet metal, shaped to finish the uppermost portion of the unit in accord with the plane face, boxlike contour of the remainder, and to provide a reentrant, air-directing bafile I0Ia, may be applied to the top of the unit, see particularly Figs. 3 and 4.

The opening at the front of the unit of the throat formed by bafile I0-Ia may be concealed by an ornamental grill l0--2.

direct line of air flow through the air-flow passages of the latter. By positioning the former intermediate the vertical extent of the air-flow passages of the latter, full advantage of the stack effect of such air-flow passages is derived.

Accordingly, in the preferred embodiment illustrated, the radiant convector II is substantially centrally placed within the body of the radiant convector l0, extending transversely across the air-flow passages I6 thereof.

Such positioning of the radiant convector II is afforded by peripherally closed apertures I9 provided substantially centrally of each of the intermediate sections I2 and-of each of the end sections l3 and M. When the sections are assembled the apertures register to form a central passage 20 extending continuously horizontally through the body of the cast iron radiant convector Ifl across the air-flowpassages I6 thereof. Thus the air-flow passages I6 are divided into an upper and a lower set, spaced apart from each other. I

The radiant convector II 'is'advantageou'sly formed'of metal predominantly of copper content resulting in the relatively high thermal conductivity which characterizes it. A convenient construction for such copper radiant convector He. The copper tubes are joined externally by a plurality of closely spaced copper plates lld, providing extensive heat exchange surfaces and air-flow passages, numerous as compared to the stacks IS.

The size of the copper radiant .convector relative to the size of the cast iron radiant convector- II) will vary according to the requirements of particular installations. It will, however, usually be small in comparison, and have comparatively short air-flow passages. The dimensions and configuration of the apertures I9 will of course vary according to the size and configuration of radiant convector Support of the copper radiant convector within the passage 20 may be accomplished incidentally by means of supply and return piping 2| and 22, respectively, forming part of the thermal system of the invention. Such piping 2|, 22, communicates with the headers Na and Nb, respectively, for effecting circulation of a fluid thermal medium through the copper tubes A manually operable three-way valve 23, interposed in supply piping 2|, regulates flow of the fluid heating medium to the cast iron radiant convector |0 by way of the short pipe .connection 24. Return flow therefrom into return piping 22 passes through the short pipe connection 25 and the valve 26.

When'the above described heat exchange unit is utilized for heating. purposes, a suitable fluid heating medium, in the present instance hot water, is supplied to both ofthe radiant convectors Ill and II, through supply piping 2|. The heat exchange surfaces of the stacks N5 of radiant convector |0 thereupon initiate air-flow upwardly through the stacks over and in intimate contact with the heat exchange surfaces of radiant convector The high thermal conductivity of radiant convector accomplishes transfer of a considerable quantity of heat to the air flowing across its surfaces from stacks i6, and, accordingly, boosts the rate of air flow through the unit. Thus, the cooperative combination of the two types of radiant convectors provides a peculiarly effective convector heater. In addition, radiant heating occurs from the exterior panel faces thereof.

The thermal system of the invention, utilizing to the full extent the advantages of the radiant convector combination of the heat exchange unit, provides for a substantially complete range of thermal treatment of air, inclusive of heating, super-heating, and cooling, as well as for mere 'air circulation. A representative embodiment of the system is illustrated diagrammatically in Fig. 5.

Referring to Fig. 5, at 30a, 30b, and 300, are indicated-heat exchange units similar to that of Fig. 1, interconnected by suitable piping. The system may, of course, be extended as indicated by the broken endings of the piping, to include any desired number of heat exchange units.

Apparatus for supplying a fluid heating medium, in the present case hot water, may comprise a conventional type boiler indicated at 3| and a water circulator 32. They may be connected ,by supply piping 33 and return piping 34 to the piping immediately serving the various heat exchange units, such piping with its included valves being indicated as heretofore with respect to Fig. 1. e

- Arefrigerating and water cooling apparatus,

indicated diagrammatically at 35, is advantageously connected in the above described piping system by supply and return piping 36 and 31, respectively, suitable valves 38 and 39 and 38| and 39-| being provided for cutting off either the heating or the cooling apparatus while the other is in use.

When the heat exchange units are utilized for cooling, the valves 23, controlling supply of fluid thermal medium to the units, are adjusted to preclude flow into radiant convector l0 while directing flow to radiant convector l; the valves 26 are adjusted to preclude back-flow into radiant convectors I0; and the valves 38| and 39| are closed to cut off the heating apparatus 2| from communication with the piping system. Circulation of cooling fluid from apparatus 35, thus takes place through radiant convectors, exclusively.

A suitable expansion tank (not shown) is provided in the thermal system in the usual manner, and a suitable auxiliary expansion tank (not shown) is connected, as by piping 3||, with the heating apparatus per se, functioning during the time such heating apparatus is cut off from the thermal system proper. shown) may be supplied at appropriate locations for removing fluid heating and/or cooling medium from the system.

For prompting circulation of air through the heat exchange unit during its use as an air cooler, means for supplying a forced draft of air is provided,

Drain cocks (not able piping 42. An air compressor 43, which may be motivated, as illustrated, by a motor 44, is here arranged to discharge compressed air into a,reservoir 45; the latter communicating directly with thesupply piping 42. Desirably, the air is subjected to a conditioning treatment such as dehumidiflcation andfiltration in asuitable conditioning apparatus, indicated generally at 46, just prior to compression. X

The forced supply of air, conditioned or otherwise, may be effectively'utilized when the heat exchange unit is functioning-as a heater as well as when it is functioning as a cooler, or may be utilized merely for promoting air circulation in the room concerned. 7

Suitable well known thermostatic means may accomplish automatic control of heating, cooling, and air circulation according to existing room temperature.

Referring now to Figs. 6 and 7 in which an additional optional feature of the invention is' il1ustrated:the'heat exchange unit is essential-' ly the same as that appearing in Fig.1.with the addition of Venturi means adjacent the outlet opening of the unit for admixing fresh atmospheric air with the thermally treated air.

The Venturi means may take the form of tubes 50, each converging from an intake opening (not shown) communicating with a source of exterior air, as for instance a window aperture, to a nozzle opening 50a disposed in the back of the air discharge throat which leads to the air outlet I2. Suitable valve means may be provided adjacent the intake opening for regulating the amount of fresh air drawn in.

The Venturi tubes 50 may penetrate the cover Ill-l of the unit at spaced locations, see Fig. 6, from the back, see Fig. 7, or from the top, see Fig. 8, and extend to the interior of the unit through baiiie I0la. In the latter case the nozzle ends of the tube are curved to suit.

The heat exchange unit of Fig. 6 is illustrated as particularly adapted for cooling, a drip pan being secured near the base of the unit for catching moisture condensation falling from radiant convector II.

The air discharge tube heretofore described may be conveniently provided as a self sufiicient element complete with individual motor. Such type of air discharge tube is designated 52, Fig. 6, the individual motor being designated 53. With this provision for individual forced supply of air, the air compressor and its appurtenant piping and reservoir may be eliminated from the thermal system.

Speaking generally, both the heat exchange unit and the thermal system of thisinvention are unique in the art of thermal treatment of air in that a wide range .of thermal effects may be readily had with a minimum'of spacial encumbrance.

Whereas the invention has been illustrated and described with'respect to preferred embodiments thereof, it is to be definitely understood that many changes may be made without departing from the generic spirit and scope of the invention as set forth herein and in the claims that follow.

I claim:

1. A unit heat exchanger comprising radiant convector means having a relatively low thermal conductivity and air flow passages, said radiant convector means being cooperatively associated in direct air flow communication with radiant convector means having'a relatively high ther*- mal conductivity and air flow passages, the air flow passages of said radiant convectors being aligned substantially vertically, both of said radiant convector means being provided with passages for confining flow of a thermal fluid in'contact with heat exchange walls thereof.

2. A unit heat exchanger comprising radiant convector-means formed of cast iron and air flow passages, said radiant convector being -cooperatively associated in direct air flow communication with radiant convector means formed of metal, predominantly of copper content and air flow pasages, the air flow passages of said radiant convectors being aligned substantially vertically, both of said radiant convector means being provided with passages for confining flow of a thermal fluid in contact with heat exchange walls thereof.

3. A heat exchanger comprising radiant convector means having a relatively low thermal conductivity cooperatively associated with radiant convector means having a relatively high thermal conductivity, the first named means providing a plurality of relatively long, substantially vertical air-flow passages grouped in two sets spaced apart vertically from each other, the

respective, air-flow passages of one set substantially registering with the respective air-flow passages of the other set to form stacks extending from the bottom to the top of the heat .exchanger, and the last named means being disposed in the space between the said two sets and exposing extensive heat exchange surfaces to air flowing through said stacks.

4. A unit heat exchanger comprising radiant convector means having a relatively low thermal conductivity and air flow passages, said radiant convector means being cooperatively associated in direct air flow communication with radiant convector means having a relatively high thermal conductivity, and air flow passages, the air flow passages of said radiant convectors being aligned substantially vertically, both of said radiant convector means being provided with passages for confining'flow of athermal fluid in contact with heat exchange walls thereof, and structurally independent means for supplying a forced draft of air directly to the last named radiant convector means.

5. A heat exchanger comprising radiant convector means having a relatively low thermal conductivity cooperatively associated with radiant convector means having a relatively high thermal conductivity, the first named means providing a plurality of relatively long, substantially vertical air-flow passages grouped in two sets spaced apart vertically from each other, the respective air-flow passages of one set substantially registering with the respective air-flow passages of the other set to form stacks extending from the bottom to the top of the heat extively high thermal conductivity and air flow passages, the air flow passages of said radiant convectors being aligned substantially vertically,

both of said radiant convector means being pro--' vided with passages for confining flow of a thermal fluid in contact with heat exchange walls thereof, means for Supplying a forced draft of means, and Venturi means disposed in the line of flow of air from the radiant convector means -for admixing fresh air with the thermally treated air.

7. A heat exchanger comprising radiant convector means having a relatively low thermal conductivity cooperatively associated with radiant convector means having a relatively high thermal conductivity, the first named means providing a plurality of relatively long, substantially vertical air-flow passages grouped in two sets spaced apart vertically from each other,

the respective air -f low passages of one set substantially registering with the respective air-flow passages of the other set to form stacks extend-v ing from the bottom to the top of the heat exchanger, and the last named means being disposed in the space between the said two sets and exposing extensive heat exchange surfaces to air flowing through said stacks, means for supplying a forced 'draft of air directly to the last named'radiant convector means, and Ventm'i means disposed in the line of flow of air from with radiant convector means having a relaair directly to the last named radiant convector 8. A heat exchange unit comprising a radiant convector of relatively low'thermal conductivity made up of sections Whose exteriors are conflg-.

urated to provide lateral concavities extending throughout the lengths of the sections, the said concavities of adjoining units cooperating to form open ended air-flow passages of the nature of stacks extending substantially vertically throughout the height of the unit, said sections being hollow, the hollow interiors of adjoining sections communicating to afford flow of a fluid heating medium through the sections, a peripherally closed aperture intermediately located in and through each section, the apertures of adjoining sections being disposed in mutual reg;-

-istry providing an open passage extending 'substantially horizontally through the unit transversely of the said air-flow pasages, and a radiant convector of high thermal conductivity disposed within said open passage and' extending transversely of the said air-flow passages.

9. A heat exchange unit comprising a radiant convector of relatively low thermal conductivity,

having an open-ended peripherally enclosed passage extending through its body transversely -of and intermediate its height, and a plurality cepting and passing through the first named passage and communicating at their lowermost open ends with air inflow means and at their uppermost open ends with air outflow means; and a radiant convector of relatively high thermal conductivity disposed within said first named passage transversely across said air-flow passages.

10. A heat exchange unit comprising a radiant v convector of relatively low thermal conductivity having an open-ended peripherally enclosed passage extending through its body transversely of and intermediate its height, and a plurality oi open-ended peripherally enclosed air-flow passages oi the nature of stacks extending substantially vertically through its said body intercepting and passing through the first named passage and communicating at their lowermost open ends with air inflow means and at their uppermost open ends with air outflow means; a radiant convector of relatively high thermal conductivity disposed within said first named passage transversely across said air-flow passages; and Venturi means disposed in the line of flow of air from said radiant convectors for admixing fresh air with the thermally treated air.

11. A heat exchange unit comprising a radiant convec'tor of relatively low thermal conductivity and of box-like contour with substantially plane faces of unbroken continuity for providing panel radiation, said radiant convector having an open-ended peripherally enclosed passage extending through its body transversely of and intermediate its height, and a plurality of open-ended peripherally enclosed air-flow passages of the nature of stacks extending substantially vertically through its said body intercepting and passing through the first named passage and communicating at their lowermost open ends with air inflow means and at their uppermost open ends with air outflow means; and a radiant convector of relatively high thermal conductivity disposed within said first named passage transversely across said air-flow passages.

12. A heat exchange unit comprising a radiant convector of relatively low thermal conductivity and of box-like contour with substantially plane faces of unbroken continuity for providing panel radiation, said radiant convector having an openended peripherally enclosed passage extending through its body transversely of and intermediate its height, and a plurality of open-ended peripherally enclosed air-flow passages of the nature of stacks extending substantially vertically through its said body intercepting and passing through the first named passage and communicating at their lowermost open ends with air inflow means and at their uppermost open ends with air outflow means; a radiant convector of relatively high thermal conductivity disposed within said first named passage transversely across said air-flow passages; and Venturi means disposed in the line of flow of. air from said radiant convectors for admixing fresh air with the thermally treated air. 

